This invention relates to small electric motors in general and more particularly relates to means for mounting the brushes thereof.
Vacuum cleaners, hand held power tools, and other small electrically powered devices are often provided with motors having wound rotors that are energized through circuits that include carbon brushes which engage a commutator mounted on the rotor. It appears that the costs of brush mounting elements and costs of assembling these elements with other motor elements is relatively high in relation to the overall cost of the motor.
Examples of prior art brush mountings in small motors are found in U.S. Pat. No. 3,226,585 issued to E. O. Roe for Dynamo-Electric Machine Coil Retaining Means, U.S. Pat. No. 3,523,288 issued to H. A. Thompson for Brush Wear Indicator, U.S. Pat. No. 3,603,824 issued to J. Csaki for Wiring Harness for Electrical Rotary Machines, U.S. Pat. No. 3,656,016 issued to A. Jacyno and H. Botefuhr for Subframe For Power Tool Having Double Insulated Brush Holders, and U.S. Pat. No. 3,710,159 issued to M. V. Dupuis and J. R. Greer for Electric Brush and Lead Holder. An examination of the aforesaid patents indicates that in the area of brush holder constructions and mountings, the number of elements are excessive, expensive elements are required and/or assembly of these elements is unnecessarily complicated and/or costly.